Known emergency oxygen dispensing units typically comprise a case containing a tank of oxygen and an oxygen mask connected to the tank by a flexible tube whereby the oxygen can be administered directly to a human patient. The following U.S. Patents illustrate oxygen dispensing devices, cases for containing or carrying such devices, and similar equipment: Eppolito U.S. Pat. No. 4,438,764 issued Mar. 27, 1984, Eppolito U.S. Pat. No. 4,383,528 issued May 17, 1983, Ansite U.S. Pat. No. 4,506,667 issued Mar. 26, 1985, Henneman et al. U.S. Pat. No. 4,186,735 issued Feb. 5, 1980, Warncke U.S. Pat. No. 3,277,890 issued Oct. 11, 1966, Almasi U.S. Pat. No. 4,359,048 issued Nov. 16, 1982, Bartlett, Jr. U.S. Pat. No. 3,208,449 issued Sept. 28, 1965, Oetjen U.S. Pat. No. 4,019,507 issued Apr. 26, 1977, Hauff U.S. Pat. No. 4,233,972 issued Nov. 18, 1980, Jarisabka U.S. Pat. No. 4,202,330 issued May 13, 1980, Beebe U.S. Pat. No. 4,560,193 issued Dec. 24, 1985, Fitt et al. U.S. Pat. No. 3,179,119 issued Apr. 20, 1965, McDonough U.S. Pat. No. 3,292,617 issued Dec. 20, 1966, van Amerongen et al. U.S. Pat. No. 3,804,280 issued Apr. 16, 1974, Warncke U.S. Pat. No. 3,483,887 issued Dec. 16, 1969, Cowley U.S. Pat. No. 3,505,997 issued Apr. 14, 1970, Haas U.S. Pat. No. 3,616,436 issued Oct. 26, 1971, Dann U.S. Pat. No. 3,507,297 issued Apr. 21, 1970, and Vernon U.S. Pat. No. 3,615,250 issued Oct. 26, 1971. In particular, Stewart U.S. Pat. No. 4,109,828, issued Aug. 29, 1978, and Berndt U.S. Pat. No. 2,831,607 issued Apr. 22, 1958, disclose inhalation apparatus housed within a substantially rectangular case having an access opening with a hinged cover. Such designs are representative of emergency oxygen units presently being sold, which units include a case having a cover or door which opens to reveal the oxygen mask, a dial for reading the oxygen level of the oxygen tank inside the case, and an on-off switch for turning on the oxygen supply.
Cases for such emergency oxygen systems are typically bulky, clumsy to use and intimidating to a potential user. For example, the inhalator according to the foregoing patent to Stewart is housed in a heavy, steel reinforced box that looks like a trunk or musical instrument case from the outside. In an emergency, it is difficult to see that this device is in fact an oxygen inhalator and can be opened at one top corner thereof. When the user succeeds in opening the door of the case for the Stewart inhalation device, the case appears to contain only an oxygen mask connected to a rubber tube, an oxygen pressure gauge built into a opaque metal plate, and an on-off switch extending through a slot in the same metal plate. No oxygen tank can be seen, and a panicked user might look into the case and believe that the tank is missing. The gauge of this device also actuates only when the on-off switch is in the on position, giving the false impression that the tank is empty (zero pressure) when the on-off switch is in the off position.
Other commercial inhalator designs suffer similar defects. Some are designed identically to musical instrument cases and could easily be mistaken for such. Others have multiple hinged doors and are so complex that they resemble "magic boxes" used by magicians. Still other designs are in the form of loose fabric backpacks which may be difficult to access in the event of an emergency and do not simplify the use of the inhalation apparatus for the user.
The present invention attempts to remedy the defects in prior art inhalators (oxygen dispensers) and similar gas dispensing devices, particularly in the design of the case which houses the gas tank and inhalation apparatus.